"I am not just proud, I am very, very proud," said one voter, a 65-year-old man.

TUNIS, Tunisia, Dec. 21 (UPI) -- Tunisia, the country that triggered the Arab Spring, is poised to elect its first democratically chosen president, as Tunisians flocked to the polls on Sunday in a run-off election.

Beji Caid Essebsi is the favorite to secure the presidency. Essebsi is a member of the secular-leaning Nidaa Tounes party, and is the challenger most likely to unseat interim leader Moncef Marzouki. He won the first round with 39 percent of the vote.

The tallying of the votes and selection of a new leader will conclude Tunisia's transition to democracy. The North African nation was the first to dispose of its leader in 2011, an event that had a domino-like effect in the region, precipitating a series of uprisings -- in Egypt, Libya, Yemen, Syria, Bahrain and elsewhere.

The 88-year-old Essebsi has promised stability and experience. He is an established politician, having served under Tunisia's now-disposed President Zine el-Abedine Ben Ali, as well as the country's first post-independence leader, Habib Bourguiba.

Essebsi and Marzouki, a 67-year-old human rights activist previously forced into exile under Ben Ali's regime, are a study in contrasts. Whereas Essebsi's support is concentrated along the coast, among wealthy communities, Marzouki is popular among the south's poorer, more conservative regions.

The vote has been monitored by international organizers, but is also being closely watched by Tunisia's own citizens. Thousands of Tunisians, who, sporting official blue vests, have walked from polling place to polling place filling out reports and noting any problems.

"I am not just proud, I am very, very proud," one voter, a 65-year-old man, told BBC News. "I never voted under dictatorship, this is the first time for me."

Despite the best efforts of some politicians -- including those in the moderate Islamist Ennahda party, which chose not to field a candidate -- the race has re-exposed tensions inside the country. Essebsi's popularity has been characterized as a victory of secular politics over Islamic interests, Marzouki is dismissive of such a narrative.

Marzouki points to Essebsi's role in the government that forced him into exile. "Beji Caid Essebsi has nothing to do with democracy," he said. "He has always been part of the dictatorship."

Essebsi has enjoyed support from left-leaning journalists, with a number of newspapers endorsing the secularist. But critics maintain that he is a symbol (if not an architect) of the country's corrupt, authoritarian past.

Marzouki is concerned about losing the election, but he's more concerned about the political escalation that could follow.

"It will be a confrontation between corrupt dictatorship and radical Islamists," he said. "These will be the main key players, and we as democrats and human rights activists will be thrown away. And this will be a huge confrontation. This will be terrible for the whole Arab world."